Organic light-emitting display device and method of manufacturing the same

ABSTRACT

An organic light-emitting display device includes a substrate having a display area surrounding a through area, and a peripheral area between the through and display areas, a light-emitting element on the display area, a first dam on the peripheral area and surrounding the through area, a first protruding pattern on the first dam and protruding toward the display area from the first dam to define an undercut region, a boundary portion extending from the display area toward the first dam, the boundary portion being spaced apart from the first dam to define a first receiving space therebetween, and an encapsulation layer continuously extending from the display area to the peripheral area, the encapsulation layer including at least one organic layer with a first filling portion filling at least part of the first receiving space and protruding toward the first dam to be aligned with the undercut region.

CROSS-REFERENCE TO RELATED APPLICATION

Korean Patent Application No. 10-2018-0015724, filed on Feb. 8, 2018, inthe Korean Intellectual Property Office, and entitled: “OrganicLight-Emitting Display Device and Method of Manufacturing the Same,” isincorporated by reference herein in its entirety.

BACKGROUND 1. Field

Exemplary embodiments relate to a display device. More particularly,exemplary embodiments relate to an organic light-emitting display deviceand a method of manufacturing an organic light-emitting display device.

2. Description of the Related Art

Recently, organic light-emitting display devices are receiving attentionas display devices displaying images. The organic light-emitting displaydevice is able to emit light, while also having reduced weight andthickness because an individual light source may be omitted.Furthermore, the organic light-emitting display device has additionaladvantageous characteristics, e.g., low power consumption, highbrightness, high response speed, etc.

SUMMARY

According to an exemplary embodiment, an organic light-emitting displaydevice includes a through area, a display area surrounding the througharea and including a light-emitting element array, and a peripheral areabetween the through area and the display area. The organiclight-emitting display device includes a first dam structure, a firstprotruding pattern and a thin film encapsulation layer. The first damstructure is disposed on the peripheral area and has a shape surroundingthe through area. The first protruding pattern is disposed on the firstdam structure and protrudes toward the display area from the first damstructure to form an undercut. The thin film encapsulation layercontinuously extends from the display area to the peripheral area andincludes at least one organic layer. The organic layer includes a firstfilling portion filling at least a portion of a first receiving spacebetween the first dam structure and a boundary portion extending fromthe display area. The first filling portion protrudes toward the firstdam structure to be aligned with the undercut.

In an exemplary embodiment, the organic light-emitting display devicefurther includes a second protruding pattern disposed on the boundaryportion and protruding toward the through area from the boundary portionto form an undercut

In an exemplary embodiment, the organic light-emitting display devicefurther includes a second dam structure disposed between the first damstructure and the through area and having a shape surrounding thethrough area, and a third protruding pattern disposed on the second damstructure and protruding toward at least the first dam structure to forman undercut.

In an exemplary embodiment, the second dam structure has a height largerthan a height of the first dam structure.

In an exemplary embodiment, the organic light-emitting display devicefurther includes a common layer extending continuously from the displayarea to be disposed on the peripheral area. The common layer isdisconnected at least between the first dam structure and the firstreceiving space.

In an exemplary embodiment, the common layer includes at least oneselected from the group consisting of a metal, a lithium compound and anorganic-light emitting material.

In an exemplary embodiment, the organic light-emitting display devicefurther includes a second dam structure disposed between the first damstructure and the through area and having a shape surrounding thethrough area. The first protruding pattern is disposed continuously onthe first dam structure and the second dam structure to cover a secondreceiving space between the first dam structure and the second damstructure.

In an exemplary embodiment, the first protruding pattern has a recessthat is caved inwardly from an outer boundary of the first protrudingpattern, in a plan view.

In an exemplary embodiment, the first dam structure includes an inletconnecting the first receiving space to the second receiving space.

In an exemplary embodiment, the organic layer of the thin filmencapsulation layer further includes a second filling portion filling atleast a portion of the second receiving space.

In an exemplary embodiment, the first protruding pattern includes aninorganic material.

According to an exemplary embodiment, a method of manufacturing anorganic light-emitting display device is provided. According to themethod, a boundary portion and a dam structure spaced apart from theboundary portion is formed on a peripheral area between a through areaand a display area. The boundary portion extends from the display area.A sacrificial pattern adjacent to the dam structure is formed. Aprotruding pattern is formed to be disposed continuously on thesacrificial pattern and the dam structure. The sacrificial pattern isremoved to form a receiving space and an undercut under the protrudingpattern. A thin film encapsulation layer continuously extending from thedisplay area to the peripheral area and including at least one organiclayer is formed. The organic layer of the thin film encapsulation layerincludes a filling portion filling at least a portion of the receivingspace and protruding toward the dam structure to be aligned with theundercut.

According to an exemplary embodiment, an organic light-emitting displaydevice includes a through area, a display area surrounding the througharea and including a light-emitting element array, and a peripheral areabetween the through area and the display area. The organiclight-emitting display device includes an undercut structure disposed onthe peripheral area and having a shape surrounding the through area, anda thin film encapsulation layer continuously extending from the displayarea to the peripheral area and including at least one organic layer.The organic layer includes a filling portion filling at least a portionof a receiving space between the undercut structure and the displayarea, and aligned with the undercut.

BRIEF DESCRIPTION OF THE DRAWINGS

Features will become apparent to those of skill in the art by describingin detail exemplary embodiments with reference to the attached drawings,in which:

FIGS. 1A and 1B illustrate schematic plan views of an organiclight-emitting display device according to an exemplary embodiment.

FIG. 2 illustrates a cross-sectional view of a display area DA of FIG.1A.

FIG. 3 illustrates an enlarged cross-sectional view of region ‘A’ ofFIG. 2.

FIG. 4 illustrates an enlarged plan view of a through area and aperipheral area of FIG. 1A.

FIGS. 5A, 5B, 5C and 6 illustrate cross-sectional views along line I-I′of FIG. 4.

FIGS. 7A to 7G illustrate cross-sectional views of stages in a method ofmanufacturing an organic light-emitting display device according to anexemplary embodiment.

FIGS. 8A and 8B illustrate enlarged cross-sectional views of asacrificial pattern and a protruding pattern in a method ofmanufacturing an organic light-emitting display device.

FIG. 9 illustrates an enlarged plan view of a through area and aperipheral area of an organic light-emitting display device according toan exemplary embodiment.

FIG. 10 illustrates an enlarged plan view of a protruding pattern of anorganic light-emitting display device according to an exemplaryembodiment.

FIGS. 11A to 11E illustrate cross-sectional views along line II-IF ofFIG. 9 of stages in a method of manufacturing an organic light-emittingdisplay device according to an exemplary embodiment.

DETAILED DESCRIPTION

Example embodiments will now be described more fully hereinafter withreference to the accompanying drawings; however, they may be embodied indifferent forms and should not be construed as limited to theembodiments set forth herein. Rather, these embodiments are provided sothat this disclosure will be thorough and complete, and will fullyconvey exemplary implementations to those skilled in the art.

In the drawing figures, the dimensions of layers and regions may beexaggerated for clarity of illustration. It will also be understood thatwhen a layer or element is referred to as being “on” another layer orsubstrate, it can be directly on the other layer or substrate, orintervening layers may also be present. In addition, it will also beunderstood that when a layer is referred to as being “between” twolayers, it can be the only layer between the two layers, or one or moreintervening layers may also be present. Like reference numerals refer tolike elements throughout.

Hereinafter, a schematic planar structure of an organic light-emittingdisplay device according to an exemplary embodiment will be explainedwith reference to FIGS. 1A and 1B.

FIGS. 1A and 1B are plan views schematically illustrating an organiclight-emitting display device according to an exemplary embodiment. FIG.1A illustrates an organic light-emitting display device having acircular planar shape, and FIG. 1B illustrates an organic light-emittingdisplay device having a rectangular planar shape. However, exemplaryembodiments are not limited thereto, and may have various shapes.

Referring to FIGS. 1A and 1B, an organic light-emitting display devicemay include a display area DA, a through area TA, and a peripheral areaPA. For example, as illustrated in FIGS. 1A and 1B, the through area TAmay penetrate through the display area DA, and the peripheral area PAmay completely surround a perimeter of the through area TA. For example,the through area TA may be centered with respect to the display area DA(FIG. 1A) or at an edge of the display area DA (FIG. 1B).

On the display area DA, a plurality of pixels emitting light may bedisposed to display an image. For example, the display area DA mayinclude an array of organic light-emitting diodes.

In the through area TA, an additional device, e.g., a camera, a sensor,a speaker or the like, may be disposed to add functions to the organiclight-emitting display device. For example, a hole may be formed througha substrate and structures thereon to form the through area TA (e.g.,FIG. 5A). A method for forming the through hole will be more fullyexplained below.

Even though FIGS. 1A and 1B show the through area TA as having asubstantially circular shape, exemplary embodiments are not limitedthereto. For example, the through area TA may have a polygonal shape,e.g., a rectangular shape, a triangular shape, or the like.

The peripheral area PA may be disposed between the display area DA andthe through area TA. Thus, the peripheral area PA may surround thethrough area DA, and the display area DA may surround the peripheralarea PA. Furthermore, a driving circuit for providing driving signals,e.g., a data signal, a gate signal or the like, to the pixels may bedisposed on the peripheral area PA.

FIG. 2 is a cross-sectional view illustrating the display area DA ofFIG. 1A. FIG. 3 is an enlarged cross-sectional view of the region ‘A’ inFIG. 2.

Referring to FIGS. 2 and 3, each pixel of the pixels disposed on thedisplay area DA may include a driving transistor on a base substrate110, an organic light-emitting diode electrically connected to thedriving transistor, and a thin film encapsulation layer 190 covering theorganic light-emitting diode. The driving transistor may include anactive pattern AP, a gate electrode GE overlapping the active patternAP, a source electrode SE electrically connected to the active patternAP, and a drain electrode DE electrically connected to the activepattern AP and spaced apart from the source electrode SE.

For example, the base substrate 110 may include glass, quartz, silicon,a polymer or the like. For example, the polymer may include polyethyleneterephthalate, polyethylene naphthalate, polyether ketone,polycarbonate, polyarylate, polyether sulfone, polyimide or acombination thereof.

A buffer layer 120 may be disposed on the base substrate 110. The bufferlayer 120 may prevent or reduce penetration of impurities, humidity, orexternal gas from underneath of the base substrate 110, and mayplanarize an upper surface of the base substrate 110. For example, thebuffer layer 120 may include an inorganic material, e.g., oxide, nitrideor the like.

The active pattern AP may be disposed on the buffer layer 120. Theactive pattern AP may overlap the gate electrode GE. For example, theactive pattern AP may include a semiconductor material, e.g., amorphoussilicon, polycrystalline silicon (polysilicon), oxide semiconductor orthe like. For example, when the active pattern AP includes polysilicon,at least a portion of the active pattern AP may be doped withimpurities, e.g., n-type impurities or p-type impurities.

A first insulation layer 130 may be disposed on the active pattern AP.For example, the first insulation layer 130 may include silicon oxide,silicon nitride, silicon oxynitride, silicon carbide, silicon oxycarbideor a combination thereof. Furthermore, the first insulation layer 130may include an insulating metal oxide, e.g., aluminum oxide, tantalumoxide, hafnium oxide, zirconium oxide, titanium oxide or the like. Forexample, the first insulation layer 130 may have a single-layerstructure or a multiple-layer structure including, e.g., silicon nitrideand/or silicon oxide.

The gate electrode GE may be disposed on the first insulation layer 130.For example, the gate electrode GE may include gold (Au), silver (Ag),aluminum (Al), copper (Cu), nickel (Ni), platinum (Pt), magnesium (Mg),chromium (Cr), tungsten (W), molybdenum (Mo), titanium (Ti), tantalum(Ta) or an alloy thereof, and may have a single-layer structure or amultiple-layer structure including different metal layers.

A second insulation layer 140 may be disposed on the gate electrode GEand the first insulation layer 130. For example, the second insulationlayer 140 may include silicon oxide, silicon nitride, siliconoxynitride, silicon carbide, silicon oxycarbide or a combinationthereof. Furthermore, the second insulation layer 140 may include aninsulating metal oxide, e.g., aluminum oxide, tantalum oxide, hafniumoxide, zirconium oxide, titanium oxide or the like.

A data metal pattern including the source electrode SE and the drainelectrode DE may be disposed on the second insulation layer 140. Thesource electrode SE and the drain electrode DE may pass through thefirst insulation layer 130 and the second insulation layer 140 tocontact the active pattern AP, respectively. For example, the sourceelectrode SE and the drain electrode DE may include gold (Au), silver(Ag), aluminum (Al), copper (Cu), nickel (Ni), platinum (Pt), magnesium(Mg), chromium (Cr), tungsten (W), molybdenum (Mo), titanium (Ti),tantalum (Ta) or an alloy thereof, and may have a single-layer structureor a multiple-layer structure including different metal layers.

A third insulation layer 150 may be disposed on the data metal patternand the second insulation layer 140. For example, the third insulationlayer 150 may include an inorganic insulation material, an organicinsulation material or a combination thereof. For example, the organicinsulation material may include polyimide, polyamide, acrylic resin,phenol resin, benzocyclobutene (BCB) or the like.

A first electrode EL1 of the organic light-emitting diode may bedisposed on the third insulation layer 150. In an exemplary embodiment,the first electrode EL1 may function as an anode. For example, the firstelectrode EL1 may be formed as a transmitting electrode or a reflectingelectrode according to an emission type of the display device. When thefirst electrode EL1 is a transmitting electrode, the first electrode EL1may include, e.g., indium tin oxide, indium zinc oxide, zinc tin oxide,indium oxide, zinc oxide, tin oxide or the like. When the firstelectrode EL1 is a reflecting electrode, the first electrode EL1 mayinclude, e.g., gold (Au), silver (Ag), aluminum (Al), copper (Cu),nickel (Ni), platinum (Pt), magnesium (Mg), chromium (Cr), tungsten (W),molybdenum (Mo), titanium (Ti) or a combination thereof, and may have astack structure further including the material that may be used for thetransmitting electrode.

A pixel-defining layer 160 may be disposed on the third insulation layer150. The pixel-defining layer 160 may include an opening that exposes atleast a portion of the first electrode EL1. For example, thepixel-defining layer 160 may include an organic insulation material. Forexample, the pixel-defining layer 160 and the third insulation layer 150may be formed by coating a photoresist composition including an organicinsulation material and patterning a coating layer usingexposure-development processes.

A common layer 180 may be disposed on the pixel-defining layer and thefirst electrode EL1. The common layer 180 may include at least one layerextending continuously across a plurality of pixels on the display areaDA. Thus, the common layer 180 may be formed substantially in the entiredisplay area DA.

For example, referring to FIG. 3, the common layer 180 may include anorganic light-emitting layer 182, a second electrode EL2, a cappinglayer 184, and a blocking layer 186. For example, the common layer 180may include at least one of a metal, a lithium compound, and anorganic-light emitting material.

The organic light-emitting layer 182 may be disposed on the firstelectrode EL1. The organic light-emitting layer 182 includes at least alight-emitting layer 182 a, and may further include functional layers182 b and 182 c contacting the light-emitting layer 182 a. For example,the organic light-emitting layer 182 may include at least one of a firstfunctional layer 182 b disposed between the light-emitting layer 182 aand the first electrode EL1, and a second functional layer 182 cdisposed between the light-emitting layer 182 a and the second electrodeEL2. For example, the first functional layer 182 b may include at leastone of a hole injection layer (HIL) and a hole transporting layer (HTL).The second functional layer 182 c may include at least one of anelectron transporting layer (ETL) and an electron injection layer (EIL).For example, the organic light-emitting layer 182 may include a lowmolecular weight organic compound or a high molecular weight organiccompound.

In an exemplary embodiment, the organic light-emitting layer 182 mayemit a red light, a green light or a blue light. In another exemplaryembodiment, the organic light-emitting layer 182 may emit a white light.The organic light-emitting layer 182 emitting a white light may have amultiple-layer structure including a red-emitting layer, agreen-emitting layer and a blue-emitting layer, or a single-layerstructure including a mixture of a red-emitting material, agreen-emitting material and a blue-emitting material.

The second electrode EL2 may be disposed on the organic light-emittinglayer 182. In an exemplary embodiment, the second electrode EL2 mayfunction as a cathode. For example, the second electrode EL2 may beformed as a transmitting electrode or a reflecting electrode accordingto an emission type of the display device. For example, when the secondelectrode EL2 is a transmitting electrode, the second electrode EL2 mayinclude lithium (Li), calcium (Ca), lithium fluoride (LiF), aluminum(Al), magnesium (Mg), or a combination thereof, and the display devicemay further include a sub electrode or a bus electrode line, which mayinclude, e.g., indium tin oxide, indium zinc oxide, zinc tin oxide,indium oxide, zinc oxide, tin oxide, or the like.

The capping layer 184 may be disposed on the second electrode EL2. Thecapping layer 184 may protect the organic light-emitting diode and maypromote the light generated by the organic light-emitting diode to exitoutwardly.

For example, the capping layer 184 may include an inorganic material oran organic material. For example, the inorganic material may includezinc oxide, tantalum oxide, zirconium oxide, titanium oxide or the like.For example, the organic material may includepoly(3,4-ethylenedioxythiophene), PEDOT),4,4′-bis[N-(3-methylphenyl)-N-phenylamino]biphenyl(TPD),4,4′,4″-tris[(3-methylphenyl)phenylamino]triphenylamine (m-MTDATA),1,3,5-tris[N,N-bis(2-methylphenyl)-amino]-benzene (o-MTDAB),1,3,5-tris[N,N-bis(3-methylphenyl)-amino]-benzene (m-MTDAB) or the like.

The blocking layer 186 may be disposed on the capping layer 184. Theblocking layer 186 may prevent damage to the organic light-emittingdiode by plasma or the like from later processes. For example, theblocking layer 186 may include lithium fluoride, magnesium fluoride,calcium fluoride or the like.

The common layer 180 may include a portion of the organic light-emittinglayer 182, the second electrode EL2, the capping layer 184, and theblocking layer 186. For example, the organic light-emitting layer 182may be formed as a pattern corresponding to each pixels by an inkjetmethod or the like, e.g., the organic light-emitting layer 182 mayinclude a plurality of discrete patterns respectively corresponding tothe plurality of pixels, while each of the second electrode EL2, thecapping layer 184, and the blocking layer 186 may be formed continuouslyover the plurality of pixels.

The thin film encapsulation layer 190 may be disposed on the commonlayer 180. The thin film encapsulation layer 190 may have a stackstructure of an inorganic layer and an organic layer. For example, thethin film encapsulation layer 190 may include a first inorganic layer192, a second inorganic layer 196, and an organic layer 194 disposedbetween the first and second inorganic layers 192 and 196.

For example, the organic layer 194 may include a cured resin, e.g.,poly(meth)acrylate or the like. For example, the cured resin may beformed from cross-linking reaction of monomers. For example, the firstand second inorganic layers 192 and 196 may include an inorganicmaterial, e.g., silicon oxide, silicon nitride, silicon carbide,aluminum oxide, tantalum oxide, hafnium oxide, zirconium oxide, titaniumoxide or the like.

Exemplary embodiments are not limited to the above-explainedconfiguration of the thin film encapsulation layer 190. For example, thethin film encapsulation layer 190 may include at least two organiclayers or at least three inorganic layers.

FIG. 4 is an enlarged plan view illustrating the through area TA and theperipheral area PA of FIG. 1A. FIGS. 5A, 5B and 5C are cross-sectionalviews along line I-I′ of FIG. 4. It is noted that FIGS. 5A, 5B and 5Cmay be considered as an extension of the right side of FIG. 2.

Referring, to FIGS. 4 and 5A, a dam structure is disposed on theperipheral area PA to surround the through area TA. For example, a firstdam structure DM1 and a second dam structure DM2 may be disposed on theperipheral area PA. The second dam structure DM2 may be disposed betweenthe first dam structure DM1 and the through area TA. In anotherexemplary embodiment, the dam structures may have a shape partiallysurrounding the through area TA.

On the peripheral area PA, the buffer layer 120, the first insulationlayer 130, and the second insulation layer 140, which, e.g.,continuously, extend from the display area DA, may be disposed on thebase substrate 110. The first dam structure DM1 and the second damstructure DM2 may be disposed on the second insulation layer 140.Furthermore, a boundary portion 166, which extends from the display areaDA, may be disposed on the peripheral area PA. The boundary portion 166may be an edge of the insulation layer extending from the display areaDA.

The first dam structure DM1 and the second dam structure DM2 may preventa monomer from moving toward the through area TA in the process offorming the organic layer 194 of the thin film encapsulation layer 190.

In an exemplary embodiment, a height of the second dam structure DM2 maybe larger than a height of the first dam structure DM1, e.g., relativelyto a top surface of the base substrate 110. For example, the second damstructure DM2 having a height larger than a height of the first damstructure DM1 may stably prevent the monomer flowing over the first damstructure DM1 from further moving toward the through are TA. However,exemplary embodiments are not limited thereto, and a height of thesecond dam structure DM2 may be substantially equal to or less than aheight of the first dam structure DM1.

The second dam structure DM2 may have a stack structure to have a heightlarger than the height of the first dam structure DM1. For example, thesecond dam structure DM2 may have a first supporting portion 152 and asecond supporting portion 164 disposed on the first supporting portion152.

The boundary portion 166, the first dam structure DM1, and the seconddam structure DM2 may be parts of a layer structure disposed on thedisplay area DA or may be formed therefrom. For example, the boundaryportion 166, the first dam structure DM1, and the second supportingportion 164 of the second dam structure DM2 may be formed from a samelayer as the pixel-defining layer 160, e.g., the boundary portion 166may be an extension of the pixel-defining layer 160 in the peripheralarea PA. Furthermore, the first supporting portion 152 may be formedfrom a same layer as the third insulation layer 150 of the display areaDA. In an exemplary embodiment, the boundary portion 166, the first damstructure DM1, and the second dam structure DM2 may include an organicmaterial. However, exemplary embodiments are not limited thereto, andthe boundary portion 166 and the first and second dam structures DM1 andDM2 may be formed from various materials and various combination oflayer structures.

Protruding patterns may be respectively formed on the first and seconddam structures DM1 and DM2, e.g., to protrude horizontally along thex-direction beyond the first and second dam structures DM1 and DM2. Theprotruding patterns may protrude from, e.g., beyond, a side surface ofthe first and second dam structures DM1 and DM2 disposed under theprotruding patterns to form an undercut region under the protrudingpatterns.

For example, as illustrated in FIG. 5A, a first protruding pattern 172may be disposed on the first dam structure DM1. The first protrudingpattern 172 may protrude along the xi direction from the first damstructure Dm1 at least toward the display area DA or the boundaryportion 166 to form an undercut region UC. Furthermore, the firstprotruding pattern 172 may protrude toward the through area TA to formundercut regions UC at both sides of the first dam structure DM1 alongthe x direction. For example, the first protruding pattern 172 may havea flat shape, and a width of the first protruding pattern 172 along thex-direction may be larger than a width of the first dam structure DM1along the x-direction, e.g., so an edge of the first protruding pattern172 may overhang the entire perimeter of the first dam structure DM1 todefine the undercut region UC to surround the first dam structure DM1under the overhanging edge (a portion of the undercut region UC iscircled on the right side of the first dam structure DM1 in FIG. 5A).

For example, as further illustrated in FIG. 5A, a second protrudingpattern 176 may be disposed on the boundary portion 166. The secondprotruding pattern 176 may have a flat shape, and may protrude along thex direction from the boundary portion 166 at least toward the througharea TA or the first dam structure DM1 to form an undercut region.

For example, as further illustrated in FIG. 5A, a third protrudingpattern 174 may be disposed on the second dam structure DM2. Forexample, the third protruding pattern 174 may protrude along the xdirection from the second dam structure DM2 at least toward the displayarea DA or the first dam structure DM1 to form an undercut region. Forexample, as illustrated in FIG. 5A, the third protruding pattern 174 maybe conformal on the second supporting portion 164 of the second damstructure DM2, so a portion of the third protruding pattern 174 along asurface of the second supporting portion 164 facing the first damstructure DM1 may define the undercut region thereunderneath.

The common layer 180 may be disposed on the peripheral area PA, e.g.,the common layer 180 may extend from the display area DA to theperipheral area PA. The common layer 180 may be disposed on the entiretyof the peripheral area PA. For example, the common layer 180 may bedisposed on the first through third protruding patterns 172, 174 and176. A portion of the common layer 180 be disposed on an upper surfaceof the second insulation layer 140, e.g., between the boundary portion166 and the first dam structure DM1 and between the first and second damstructures DM1 and DM2. As illustrated in FIG. 5A, the common layer 180may not be continuous, e.g., may include disconnected or discontinuousportions at different heights and on different elements to cover theentirety of the peripheral area PA. For example, a portion of the commonlayer 180 disposed on the upper surface of the second insulation layer140 may be disconnected with a portion of the common layer 180 disposedon the protruding patterns 172, 174 and 176.

The thin film encapsulation layer 190 extends from the display area DAto be disposed on the peripheral area PA. In an exemplary embodiment,the organic layer 194 of the thin film encapsulation layer 190 may bedisposed partially on the peripheral area PA, and the first inorganiclayer 192 and the second inorganic layer 196 of the thin filmencapsulation layer 190 may be disposed entirely on the peripheral areaPA.

For example, the first inorganic layer 192 of the thin filmencapsulation layer 190 may continuously extend along an upper surfaceof the common layer 180 and side surfaces of the dam structures DM1 andDM2.

The organic layer 194 of the thin film encapsulation layer 190 may havea filling portion 194 a that fills at least a portion of a firstreceiving space between the boundary portion 166 and the first damstructure DM1. Because the undercut region UC is formed by the firstprotruding pattern 172 disposed on the first dam structure DM1, thefilling portion 194 a may include a lower portion 194 a_1 having alarger width along the x direction than an upper portion 194 a 2according to a shape of the undercut region UC. For example, the fillingportion 194 a may have a shape protruding toward the undercut region UCalong the x direction. As a result, the filling portion 194 a may bealigned and combined with the undercut region UC of the first damstructure DM1 along the y direction.

The second inorganic layer 196 of the thin film encapsulation layer 190may continuously extend along an upper surface of the organic layer 194and an upper surface of the first inorganic layer 192. For example, asillustrated in FIG. 5A, the first and second inorganic layers 192 and196 may be in direct contact with each other beyond the edge of theorganic layer 194, i.e., on the first and second dam structures DM1 andDM2.

Combination of the first dam structure DM1 and the organic layer 194 ofthe thin film encapsulation layer 190 may function as an anchor. Thus,when an external force is applied to the thin film encapsulation layer190, separation of the organic layer 194 from the first inorganic layer192 may be prevented, e.g., as the lower portion 194 a_1 of the fillingportion 194 a of the organic layer 194 is anchored against the firstinorganic layer 192 and the undercut region UC. Furthermore, suchstructure may prevent reflowing in the process of forming the organiclayer 194 to improve reliability of a display device. Such advantageswill be more fully explained below.

In an exemplary embodiment, the second protruding pattern 176 may bedisposed on the boundary portion 166 to form another undercut region, asdescribed previously. Thus, the filling portion 194 a of the organiclayer 194 may protrude toward the undercut region under the boundaryportion 166. For example, effects of combined force increased by theundercut region and the filling portion 194 a may be different dependingon a direction, along which the protective tape is stripped. Accordingto the exemplary embodiment, undercut regions combination is formed atboth sides of the filling portion 194 a. Thus, combination force may beincreased in various directions.

However, exemplary embodiments are not limited thereto. For example, asillustrated in FIG. 5B, the filling portion 194 a may partially fill thefirst receiving space between the boundary portion 166 and the first damstructure DM1. For example, undercut region combination may be formed atone side of the filing portion 194 a, which is adjacent to the displayarea DA.

Furthermore, the organic layer 194 may extend over the first damstructure DM1 toward a second receiving space between the first damstructure DM1 and the second dam structure DM2. Therefore, an additionalfilling portion may be formed in the second receiving space. Forexample, as illustrated in FIG. 5C, the additional filling portion 194 bdisposed in the second receiving space may be combined with an undercutregion formed by the first protruding pattern 172 or the thirdprotruding pattern 174 to increase the combination force of the organiclayer 194.

As illustrated in FIGS. 5A, 5B and 5C, a through hole TH may be formedat the organic light-emitting display device to define the through areaTA. In an exemplary embodiment, all structures including the basesubstrate 110 may be removed from the through area TA. However,exemplary embodiments are not limited thereto. For example, asillustrated in FIG. 6, after the through hole TH is formed, the basesubstrate 110 may remain. In yet another example, the base substrate 110may be removed, and a supporting substrate 112 may be provided in thethrough area TA to replace the removed base substrate 110.

Hereinafter, a method of manufacturing an organic light-emitting displaydevice according to an exemplary embodiment will be explained withreference to accompanying drawings. FIGS. 7A to 7G are cross-sectionalviews illustrating stages in a method of manufacturing an organiclight-emitting display device according to an exemplary embodiment.FIGS. 8A and 8B are enlarged cross-sectional views illustrating asacrificial pattern and a protruding pattern in the method ofmanufacturing an organic light-emitting display device.

Referring to FIGS. 2 and 7A, the first dam structure DM1 and the seconddam structure DM2 are formed on the base substrate 110 including thedisplay area DA, the through area TA, and the peripheral area PA. Theperipheral area PA may be disposed between the display area DA and thethrough area TA, as discussed previously and illustrated in FIGS. 1A and1B.

In detail, the buffer layer 120 and first and second insulation layers130 and 140 (hereinafter referred to as “insulation layers 120 through140”) may be disposed on the base substrate 110, e.g., during formationof the driving transistor illustrated in FIG. 2, and may extend, e.g.,continuously, from the display area DA to the peripheral area PA and tothe through area TA. The first dam structure DM1 and the second damstructure DM2 may be disposed on the insulation layers 120 through 140,e.g., after formation of the first electrode EL1 in the display area DA.The second dam structure DM2 may include the first supporting portion152 and the second supporting portion 164 disposed on the firstsupporting portion 152.

In an exemplary embodiment, the second dam structure DM2 may have ashape surrounding the through area TA in a plan view, and the first damstructure DM1 may have a shape surrounding the second dam structure DM2.For example, each of the first dam structure DM1 and the second damstructure DM2 may have a continuous loop shape, respectively, and theloop shapes may be concentric (FIG. 4).

The first dam structure DM1 and the second dam structure DM2 may beportions of a layer structure disposed on the display area DA or may beformed therefrom. For example, the first dam structure DM1 and thesecond supporting portion 164 of the second dam structure DM2 may beformed from a same layer, e.g., and at the same time, as thepixel-defining layer 160 in the display area DA. Furthermore, the firstsupporting portion 152 may be formed from a same layer, e.g., and at thesame time, as the third insulation layer 150 of the display area DA.

The boundary portion 166 may be disposed on the peripheral area PA, andmay extend from the display area DA. For example, the boundary portion166 may be extend from the pixel-defining layer 160 and/or the thirdinsulation layer 150 or may be formed therefrom. In an exemplaryembodiment, the boundary portion 166 may extend from the pixel-defininglayer 160.

For example, a photoresist composition may be coated on the insulationlayers, e.g., on the second insulation layer 140, and developed to formthe boundary portion 166, the first dam structure DM1, and the seconddam structure DM2 in the peripheral area PA. For example, the samephotoresist composition may be developed to simultaneously form thepixel-defining layer 160 in the display area DA.

Referring to FIG. 7B, a first sacrificial pattern SL1 is formed betweenthe boundary portion 166 and the first dam structure DM1, and a secondsacrificial pattern SL2 is formed between the first dam structure DM1and the second dam structure DM2. For example, the first sacrificialpattern SL1 and the second sacrificial pattern SL2 may be formed by aprinting method, e.g., an inkjet printing method. For example, apositive type photoresist composition or a negative type photoresistcomposition may be provided by an inkjet printing method to form thefirst sacrificial pattern SL1 and the second sacrificial pattern SL2.

Referring to FIG. 7C, protruding patterns are formed on the boundaryportion 166, the first dam structure DM1, and the second dam structureDM2. For example, the protruding patterns may include the firstprotruding pattern 172 disposed on the first dam structure DM1, thesecond protruding pattern 176 disposed on the boundary portion 166, andthe third protruding pattern 174 disposed on the second dam structureDM2.

At least a portion of the protruding pattern may be disposed on thesacrificial pattern adjacent thereto. Thus, the protruding pattern maycover at least a portion of an upper surface of the sacrificial pattern.For example, a first end of the first protruding pattern 172 may bedisposed on the first sacrificial pattern SL1, and a second end of thefirst protruding pattern 172 may be disposed on the second sacrificialpattern SL2. An end of the second protruding pattern 176 may be disposedon the first sacrificial pattern SL1. An end of the third protrudingpattern 174 may be disposed on the second sacrificial pattern SL2.

The protruding patterns 172, 174 and 176 may form undercut regions afterthe sacrificial patterns SL1 and SL2 are removed. The protrudingpatterns 172, 174 and 176 may include various materials. For example,the protruding patterns 172, 174 and 176 may include an inorganicmaterial, e.g., silicon oxide, silicon nitride, silicon carbide,aluminum oxide, tantalum oxide, hafnium oxide, zirconium oxide, titaniumoxide or the like.

When the protruding patterns 172, 174 and 176 are formed, a structure onthe display area DA needs to be protected. For example, the protrudingpatterns 172, 174 and 176 may be formed by a deposition process using amask having an opening corresponding to an area where the protrudingpatterns 172, 174 and 176 are formed.

Referring to FIG. 7D, the first sacrificial pattern SL1 and the secondsacrificial pattern SL2 are removed. For example, a developer, astripper or the like may be provided to remove the first sacrificialpattern SL1 and the second sacrificial pattern SL2.

The protruding patterns 172, 174 and 176 cover at least a portion of anupper surface of first sacrificial pattern SL1 and the secondsacrificial pattern SL2. Thus, as the first sacrificial pattern SL1 andthe second sacrificial pattern SL2 are removed, the undercut regions UCmay be formed under the protruding patterns 172, 174 and 176, e.g.,region defined by overhanging portions of the protruding patterns 172,174 and 176.

A space between the first dam structure DM1 and the boundary portion 166may be defined as a first receiving space RC1, and a space between thefirst dam structure DM1 and the second dam structure DM2 may be definedas a second receiving space RC2.

Referring to FIG. 7E, the common layer 180 may be formed on theperipheral area PA. The common layer 180 may be formed on the displayarea DA as well as on the peripheral area PA. The common layer 180 mayinclude at least one of the organic light-emitting layer 182, the secondelectrode EL2, the capping layer 184, and the blocking layer 186, asillustrated in FIG. 3.

The common layer 180 may be formed by, e.g., an inkjet printing method,a screen printing method, a deposition method or the like, and may beformed by combination of different methods. In an exemplary embodiment,the common layer 180 may be a vacuum deposition method.

The common layer 180 may be formed entirely on the peripheral area PA.For example, the common layer 180 may be formed on the protrudingpatterns 172, 174 and 176 and in the first receiving space RC1 and thesecond receiving space RC2. The common layer 180 may be disconnected byan undercut structure on the peripheral area PA. For example, a portiondisposed on the protruding patterns 172, 174 and 176 may be disconnectedwith a portion disposed in the first receiving space RC1 and the secondreceiving space RC2.

If the common layer 180 is not disconnected, humidity or the like maypenetrate into the display area from an end of the common layer 180, orseparation may be easily progressed at an interlayer interface in thecommon layer 180 o or at an interface between the common layer 180 andother layers. In an exemplary embodiment, the common layer 180 on theperipheral area PA is disconnected by the undercut structure. Thus,progression of separation or penetration of humidity may be prevented.Thus, reliability of a display device may be maintained.

Referring to FIGS. 7F and 7G, the thin film encapsulation layer 190 isformed on the peripheral area PA. The thin film encapsulation layer 190may have a stack structure in which an organic layer and an inorganiclayer are alternately stacked. The thin film encapsulation layer 190 maybe formed on the display area DA as well as on the peripheral area PA.For example, the thin film encapsulation layer 190 may include the firstinorganic layer 192, the second inorganic layer 196, and the organiclayer 194 disposed between the first and second inorganic layers 192 and196.

For example, the first inorganic layer 192 may include an inorganicmaterial, e.g., silicon oxide, silicon nitride, silicon carbide,aluminum oxide, tantalum oxide, hafnium oxide, zirconium oxide, titaniumoxide or the like, and may be formed by a chemical vaporizationdeposition method. For example, the first inorganic layer 192 may beformed conformally on an upper surface and a side surface of thestructures disposed on the peripheral area PA.

The organic layer 194 may be formed on the first inorganic layer 192.For example, a monomer composition may be provided on an upper surfaceof the first inorganic layer 192 to form the organic layer 194.

The monomer composition may include a curable monomer. For example, thecurable monomer may contain at least one curable functional group. Forexample, the curable functional group may include a vinyl group, a(meth)acrylate group, an epoxy group or the like.

For example, the curable monomer may include ethyleneglycoldi(meth)acrylate, hexanediol di(meth)acrylate, heptanedioldi(meth)acrylate, octanediol di(meth)acrylate, nonanedioldi(meth)acrylate, decanediol di(meth)acrylate, triethylpropanetri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritoltetra(meth)acrylate, dipentaerythritol tri(meth)acrylate,dipentaerythritol tetra(meth)acrylate, dipentaerythritolpenta(meth)acrylate, dipentaerythritol hexa(meth)acrylate or the like.

The monomer composition may further include an initiator such as a photoinitiator or the like.

The monomer composition may be provided on the first inorganic layer 192by, e.g., an inkjet printing method, a screen printing method or thelike. A portion of the monomer composition may flow in the firstreceiving space RC1. Thus, the organic layer 194 formed from the monomercomposition may include the filling portion 194 a filling the firstreceiving space RC1 between the first dam structure DM1 and the boundaryportion 166.

The organic layer 194 may be weakened by humidity or the like. Thus, theorganic layer 194 needs to be controlled so that a boundary of theorganic layer 194 disposed on the peripheral area PA does not have anedge exposed at the through area TA or the like. In an exemplaryembodiment, the first and second dam structures DM1 and DM2 are providedto prevent reflowing of the monomer composition in the process offorming the organic layer 194, and the undercut regions UC are formed atthe first and second dam structures DM1 and DM2. The undercut region UCincreases a length of an interface contacting the monomer composition ora wetting length to effectively prevent or substantially minimize themonomer composition from flowing over the dam structures.

The monomer composition may be preferably controlled not to flow overthe first dam structure DM1. However, even if the monomer compositionflows over the first dam structure DM1, the monomer composition may beprevented from flowing into the through area TA by the second damstructure DM2 and the undercut region UC formed by the third protrudingpattern 174. Furthermore, as the thin film encapsulation layer 190includes at least two organic layers so that the monomer composition isprovided on the second inorganic layer 196, the monomer composition maybe prevented from reflowing by the second dam structure DM2.

As described previously, the organic layer 194 has a low interfacialadhesion to the inorganic layer. However, in an exemplary embodiment,because the organic layer 194 includes the filling portion 194 adisposed between the first dam structure DM1 and the boundary portion166 and aligned with the undercut region UC of the first dam structureDM1, separation of the organic layer 194 due to an external force may beprevented.

The monomer composition may be cured in a following process to form acured resin.

The second inorganic layer 196 may be formed on the organic layer 194.The second inorganic layer 196 may include a same material as the firstinorganic layer 192 and may be formed by a same method.

In order to form the through area TA, the through hole TH correspondingto the through area TA may be formed. For example, as illustrated inFIG. 5A, the base substrate 110 and a layer structure disposed on thebase substrate 110 may be removed from the through area TA. For example,the through hole TH may be formed by a laser or the like.

In an exemplary embodiment, an undercut structure is formed on aperipheral area between a through area and a display area. Thus, acommon layer formed thereon may be disconnected, and reflowing of amonomer composition for forming an organic layer of a thin filmencapsulation layer may be effectively inhibited. Furthermore, alignmentcombination between the undercut structure and the organic layer isformed thereby preventing separation of the organic layer.

In an exemplary embodiment, a single organic layer is disposed in thefirst receiving space RC1. However, exemplary embodiments are notlimited thereto. When the thin film encapsulation layer 190 includes atleast two organic layers, at least a portion of each organic layer maybe disposed in the first receiving space RC1.

In the exemplary embodiment illustrated in FIGS. 7A to 7G, thesacrificial pattern having a same height as the dam structure isillustrated. However, exemplary embodiments are not limited thereto. Thesacrificial pattern may have various heights and combinations.Therefore, a shape of the protruding pattern formed along surfaces ofthe dam structure and the sacrificial pattern may be variously changed.

For example, as illustrated in FIG. 8A, the first sacrificial patternSL1 and the second sacrificial pattern SL2 may have a height smallerthan the first dam structure DM1. As a result, the protruding pattern172 may partially cover a side surface of the first dam structure DM1.

Furthermore, as illustrated in FIG. 8B, the first sacrificial patternSL1 may have a height smaller than the first dam structure DM1, and thesecond sacrificial pattern SL2 may have a height larger than the firstdam structure DM1. As a result, the protruding pattern 172 may have astep shape.

A length of an undercut formed by the protruding pattern 172, which maybe a protruding length of the protruding pattern 172, may beappropriately adjusted in view of a pattern shape, following processesor the like.

FIG. 9 is an enlarged plan view illustrating the through area TA and theperipheral area PA of an organic light-emitting display device accordingto an exemplary embodiment. FIG. 10 is an enlarged plan viewillustrating a protruding pattern of an organic light-emitting displaydevice according to an exemplary embodiment. FIG. 11A to FIG. 11E arecross-sectional views illustrating stages in a method of manufacturingan organic light-emitting display device according to an exemplaryembodiment along line II-IF of FIG. 9.

Referring to FIGS. 9, 10 and 11A, the boundary portion 166, the firstdam structure DM1, and the second dam structure DM2 are formed on theperipheral area PA of the base substrate 110.

In an exemplary embodiment, the second dam structure DM2 may have ashape surrounding the through area TA. The first dam structure DM1 mayhave a shape surrounding the second dam structure DM2.

In an exemplary embodiment, the first dam structure DM1 may bediscontinuously formed. For example, the first dam structure DM1 mayinclude a plurality of patterns spaced apart from each other. Adjacentpatterns may form an inlet IL therebetween. The second dam structure DM2may have a continuous loop shape.

Thereafter, the first sacrificial pattern SL1 is formed between theboundary portion 166 and the first dam structure DM1, and the secondsacrificial pattern SL2 is formed between the first dam structure DM1and the second dam structure DM2. The first sacrificial pattern SL1 andthe second sacrificial pattern SL2 may be connected to each otherthrough the inlet IL of the first dam structure DM1. Thereafter,protruding patterns are formed on the first dam structure DM1, theboundary portion 166, and the second dam structure DM2.

In an exemplary embodiment, the protruding patterns may include a firstprotruding pattern 173 disposed continuously on the first dam structureDM1 and the second dam structure DM2, and the second protruding pattern176 disposed on the boundary portion 166. The first protruding pattern173 may continuously cover an upper surface of the first dam structureDM1, an upper surface of the second sacrificial pattern SL2, and anupper surface of the second dam structure DM2. The second protrudingpattern 176 may cover a portion of an upper surface of the firstsacrificial pattern SL1.

Referring to FIG. 10, the first protruding pattern 173 may have a recess175 caved inwardly from an outer boundary in a plan view. The recess 175may overlap the inlet IL of the first dam structure DM1.

Referring to FIG. 11B, the first sacrificial pattern SL1 and the secondsacrificial pattern SL2 are removed. As the first sacrificial patternSL1 and the second sacrificial pattern SL2 are removed, an undercutregion may be formed under the protruding patterns.

The first protruding pattern 173 may protrude toward the display area DAfrom the first dam structure DM1 to form an undercut region under thefirst protruding pattern 173. The second protruding pattern 176 mayprotrude toward the through area TA from the boundary portion 166 toform an undercut region under the second protruding pattern 176. A spacebetween the first dam structure DM1 and the boundary portion 166 may bedefined as the first receiving space RC1. A space between the first damstructure DM1 and the second dam structure DM2 may be defined as thesecond receiving space RC2. Because the first protruding pattern 173 isdisposed continuously on the first dam structure DM1 and the second damstructure DM2, the first protruding pattern 173 may cover the secondreceiving space RC2.

Referring to FIG. 11C, the common layer 180 may be forming on theperipheral area PA. The common layer 180 may be formed on the displayarea DA as well as on the peripheral area PA. The common layer 180 mayinclude at least one of the organic light-emitting layer 182, the secondelectrode EL2, the capping layer 184, and the blocking layer 186, asillustrated in FIG. 3.

The common layer 180 may be disconnected by the undercut structure onthe peripheral area PA. For example, a portion disposed on theprotruding patterns 173 and 176 may be disconnected with a portiondisposed in the first receiving space RC1.

Referring to FIGS. 11D and 11E, the thin film encapsulation layer 190 isformed on the peripheral area PA. The thin film encapsulation layer 190may have a stack structure in which an organic layer and an inorganiclayer are alternately stacked. The thin film encapsulation layer 190 maybe formed on the display area DA as well as on the peripheral area PA.For example, the thin film encapsulation layer 190 may include the firstinorganic layer 192, the second inorganic layer 196, and the organiclayer 194 disposed between the first inorganic layer 192 and the secondinorganic layer 196.

The organic layer 194 may be formed on the first inorganic layer 192.For example, a monomer composition may be provided on an upper surfaceof the first inorganic layer 192.

The monomer composition may be provided on the first inorganic layer 192by, e.g., an inkjet printing method, a screen printing method or thelike. A portion of the monomer composition may flow in the firstreceiving space RC1. Furthermore, the monomer composition may flow inthe second receiving space RC2 through the inlet IL of the first damstructure DM1 and the recess 175 of the first protruding pattern 173

Thus, the organic layer 194 formed from the monomer composition mayinclude the filling portion 194 a filling the first receiving space RC1between the first dam structure DM1 and the boundary portion 166, and asecond filling portion 194 b filling the second receiving space RC2between the first dam structure DM1 and the second dam structure DM2. Asillustrated, the second filling portion 194 b may partially fill in thesecond receiving space RC2.

The above structure may consecutively receive the monomer composition inthe first receiving space RC1 and the second receiving space RC2. Thus,the monomer composition may be easily controlled. Furthermore, because aportion of the organic layer 194 is entirely covered by the firstprotruding pattern 173, effect for preventing separation of the organiclayer 194 may be enhanced.

Exemplary embodiments may be applied to various display devices that maybe used for, e.g., a television, a computer, a notebook computer, atablet computer, a smart phone, a mobile phone, a navigator, a homeappliance or the like.

By way of summation and review, in order to increase durability and tomaintain performance, the organic light-emitting display device may beencapsulated to prevent or substantially minimize influence of humidityand oxygen from the exterior. For example, the organic light-emittingdisplay device may be encapsulated by a thin film encapsulation layer.However, when a through area is formed in a display area, e.g., to add acamera, a sensor or the like, humidity may enter the display area fromthe through area, or separation may be caused at an interface of thethin film encapsulation layer or a common layer in the process ofremoving a protective tape, e.g., disposed on the thin filmencapsulation layer, from the organic light-emitting display device.

In contrast, exemplary embodiments provide an organic light-emittingdisplay device having improved reliability and a method of manufacturingthe same. That is, according to exemplary embodiments, a dam structurewith an undercut region is formed on a peripheral area between thethrough area and the display area, so that a common layer isdisconnected. Further, reflowing of a monomer composition for forming anorganic layer of the thin film encapsulation layer may be effectivelyinhibited. Furthermore, the undercut region is alignment, e.g., fittedand combined with the organic layer of the thin film encapsulation layerto prevent separation of the organic layer.

Example embodiments have been disclosed herein, and although specificterms are employed, they are used and are to be interpreted in a genericand descriptive sense only and not for purpose of limitation. In someinstances, as would be apparent to one of ordinary skill in the art asof the filing of the present application, features, characteristics,and/or elements described in connection with a particular embodiment maybe used singly or in combination with features, characteristics, and/orelements described in connection with other embodiments unless otherwisespecifically indicated. Accordingly, it will be understood by those ofskill in the art that various changes in form and details may be madewithout departing from the spirit and scope of the present invention asset forth in the following claims.

What is claimed is:
 1. An organic light-emitting display device,comprising: a base substrate including a display area surrounding athrough area, and a peripheral area between the through area and thedisplay area; a light-emitting element array on the display area of thebase substrate; a first dam structure on the peripheral area of the basesubstrate, the first dam structure having a shape surrounding thethrough area; a first protruding pattern on the first dam structure, thefirst protruding pattern protruding toward the display area from thefirst dam structure to define a first undercut region; a boundaryportion extending from the display area toward the first dam structure,the boundary portion being spaced apart from the first dam structure todefine a first receiving space therebetween; and a thin filmencapsulation layer continuously extending from the display area to theperipheral area, the thin film encapsulation layer including at leastone organic layer, wherein the organic layer includes a first fillingportion filling at least a portion of the first receiving space, thefirst filling portion protruding toward the first dam structure to bealigned with the first undercut region.
 2. The organic light-emittingdisplay device as claimed in claim 1, further comprising a secondprotruding pattern on the boundary portion and protruding toward thethrough area from the boundary portion to form a second undercut region.3. The organic light-emitting display device as claimed in claim 2,further comprising: a second dam structure between the first damstructure and the through area, the second dam structure surrounding thethrough area; and a third protruding pattern on the second dam structureand protruding toward at least the first dam structure to form a thirdundercut region.
 4. The organic light-emitting display device as claimedin claim 3, wherein the second dam structure has a height larger than aheight of the first dam structure.
 5. The organic light-emitting displaydevice as claimed in claim 1, further comprising a common layerextending continuously from the display area into the peripheral area,the common layer being discontinuous at least between the first damstructure and the first receiving space.
 6. The organic light-emittingdisplay device as claimed in claim 5, wherein the common layer includesat least one of a metal, a lithium compound and an organic-lightemitting material.
 7. The organic light-emitting display device asclaimed in claim 1, further comprising a second dam structure betweenthe first dam structure and the through area, the second dam structuresurrounding the through area, wherein the first protruding pattern iscontinuous on the first dam structure and the second dam structure tocover a second receiving space between the first dam structure and thesecond dam structure.
 8. The organic light-emitting display device asclaimed in claim 7, wherein the first protruding pattern has a recessthat is caved inwardly from an outer boundary of the first protrudingpattern, in a plan view.
 9. The organic light-emitting display device asclaimed in claim 8, wherein the first dam structure includes an inletconnecting the first receiving space to the second receiving space. 10.The organic light-emitting display device as claimed in claim 7, whereinthe organic layer of the thin film encapsulation layer further includesa second filling portion filling at least a portion of the secondreceiving space.
 11. The organic light-emitting display device asclaimed in claim 1, wherein the first protruding pattern includes aninorganic material.
 12. A method of manufacturing an organiclight-emitting display device, the method comprising: forming a boundaryportion and a dam structure spaced apart from the boundary portion on aperipheral area of a base substrate, the peripheral area being between athrough area and a display area, and the boundary portion extending fromthe display area into the peripheral area; forming a sacrificial patternadjacent to the dam structure; forming a protruding pattern continuouslyon the sacrificial pattern and the dam structure; removing thesacrificial pattern to form a receiving space and an undercut regionunder the protruding pattern; and forming a thin film encapsulationlayer continuously extending from the display area to the peripheralarea and including at least one organic layer, wherein the organic layerof the thin film encapsulation layer includes a filling portion fillingat least a portion of the receiving space and protruding toward the damstructure to be aligned with the undercut region.
 13. The method asclaimed in claim 12, wherein the dam structure includes: a first damsurrounding the through area; and a second dam surrounding the througharea and disposed between the first dam and the through area.
 14. Themethod as claimed in claim 13, wherein the sacrificial pattern includes:a first sacrificial pattern disposed between the first dam and theboundary portion; and a second sacrificial pattern disposed between thefirst dam and the second dam.
 15. The method as claimed in claim 13,wherein the protruding pattern includes: a first protruding patterndisposed on the first dam and protruding toward at least the boundaryportion; a second protruding pattern disposed on the boundary portionand protruding toward the first dam; and a third protruding patterndisposed on the second dam and protruding toward at least the first dam.16. The method as claimed in claim 13, wherein the protruding patternincludes: a first protruding pattern disposed continuously on the firstdam and the second dam and protruding toward at least the boundaryportion; and a second protruding pattern disposed on the boundaryportion and protruding toward the first dam.
 17. The method as claimedin claim 16, wherein the first dam includes an inlet connecting a firstreceiving space between the first dam and the boundary portion to asecond receiving space between the first dam and the second dam.
 18. Themethod as claimed in claim 17, wherein the organic layer of the thinfilm encapsulation layer includes: a first filling portion filling atleast a portion of the first receiving space; and a second fillingportion filling at least a portion of the second receiving space. 19.The method as claimed in claim 12, wherein forming the thin filmencapsulation layer includes: forming a first inorganic layer; providinga monomer composition on the first inorganic layer; and curing themonomer composition.
 20. An organic light-emitting display device,comprising: a base substrate including a display area surrounding athrough area, and a peripheral area between the through area and thedisplay area; a light-emitting element array on the display area of thebase substrate; an undercut structure on the peripheral area andsurrounding the through area; and a thin film encapsulation layercontinuously extending from the display area to the peripheral area, thethin film encapsulation layer including at least one organic layer,wherein the organic layer includes a filling portion filling at least aportion of a receiving space between the undercut structure and thedisplay area, and aligned with the undercut structure.